1. Field of the Invention
The present invention relates to a semiconductor memory device, and more particularly to a semiconductor memory device provided with a mode register.
2. Description of the Background Art
A synchronous DRAM (a synchronous semiconductor memory device) is provided with a mode register. An operation mode for the synchronous DRAM can be designated by setting the mode register.
In a conventional semiconductor memory device, such a mode register has been used to determine its operation mode.
In such a semiconductor memory device, however, once the operation mode has been set, it is impossible to confirm the set value in the mode register, or, to check whether a desired value has been set to the mode register or not. Therefore, in practical use, a test must be conducted to check whether the semiconductor memory device operates as desired in order to determine whether or not a desired value has been set. Such a test is laborsome and time consuming.